Metal spbat gun



F. O. ALBERTSON June 3, 1941.

' METAL' SPRAY GUN Original Filed April 30. 1936 2 sheets-sheet 14 June V3 1941 F. o. ALBERTsoN l Re. 21,814

, MTAL'SPRY GUN l v 'original Filed April so, 193e 2 sheets-sheet 2 3515976331103 77,y l1 y j 60 l Qfi 3 jj/5155 563 1 vision of an improved metal spray gunVv havin of which both the air Rouued June 1941 V l UNITED "STATES PATENT OFFICE METAL SPRAY GUN o Frans 0. Albertson, Sioux City, Iowa. assisnor to Albertson Company, Inc., Sioux City, Iowa, a

corporation o! Iowa Original N0. 2,058,653, dated October'27, 1936,

Serial No. 77,094, April 30, 1936.

Application for reissue November 3, 1937. Serial No; 172,572

28 tlaims.V (Cl. 9112.2)`

The present invention relates to metal spray guns, and is particularly concerned with devices ofthe type adapted to spray cold metal upon a prepared metal surface.

It ilnds its most effective field of use in build- `ing up dents and depressions upon the bodies of automotive vehicles without heating the body metal, and in places formerly inaccessible for repair work except by long, tedious hand labor methods.

In straightening fenders andbody parts it is not always possible to get the surface entirely smooth. If such a surface is` sanded until't is even, certain spots on the metal will be almost sanded through uptilthere is practically no metal left. This condition can now be .avoided by applying a thin layer of suitable metalj. alloy on the spot with a spray gunconstructed acl cording to the present invention, and thensanding the area to a smooth and even nish.

One of the objects of the invention is the provision of an improved metal spray gun which has provision for cooling the gun by compressed air used for the spray.

Another abject 'of the invention is thetprovitsion of an improved metal spray gun by means of which the metal may be sprayed more'eiece tively by a cold process so that the bodyoftvhe spray method is also lnecessa:

because some bodies are now insulated with iny( ammable materials.

Another object is the provision of an improved l ,complete controlA f nozzle structure for a metal spray gun of the class described, having a particular structure `adapted to withstand melting and having a shape y which is more effective than the devices of the prior art. v

Another object is the provision of an improved metal spray gun utilizing heat for the melting of the metal, which is so constructed that it is more eiectively cooled and thehandle parts are kept cooler than the devices of the.prior art.,` Another object of the invention is-the provision of an improved metal spray gun in which melted metal is sprayed by compressed air, and in which the air is also heated preliminary to its intermingling with the metal in the spray, so as to preventchilling of the melted metal by the eompressedair.

1 of const Another object of the invention is the provision of an improved metal spray gun oi the class described, in which the gun body is constructed with parts which are separated from each other to prevent heat transmission except at a plurality of spacing lugs Vor members which are used to effect the separation.

`Another object of the invention is the provision of an improved metal spray gun of the class described, vin which the handleis effectively cooled by means of an improved construction and support for the gun body on -its handle.

Other'objects and-advantages of the invention will beapparent from the following description and the accompanying drawings, in which similar characters ofY reference indicate similar parts throughout. the several views.

Referringfto the two sheets of drawings:

Fis.; is aside e1evationa1 view of the metal spray gunconstructed according to the present invention;`

Fig. `21is' a vertical sectionalview taken on a plane of theline 3--3 of Fig. 2, looking in the direction ofthe arrows, and showing the end of the, heating element housing Flshfi vertical sectional view taken on the e line 4-.4 of Fig. 2, looking in the t the arrows and showing the' details on the handle;

Fig'. 5 isy @bottom plan view'of`the` heating -element-housingV 'and a sectional vlewl taken `1 through th'eheat radiating supports on thefplane` ylooking ln'thedirecn` of the line 5 5 of Fig. 2, tion of the arrows;

Fig. 6 is a horizontal sectional `viemtaken vthrough the handle and trigger structure. onthe` plane ofthe line 6 6 of Fig.. 2, looking-inthe rdirection of the arrows;

' Figj? is a front elevational view end of the gun;

'. Fi 'l I of the nose Fig. a ,fragmentary sectional view, show- .,ing theapplication otthe tool for blowing out the metal well.

Referring to Figs. 1 and 2, the handle member I0 may be constructed of cast metal, having any i suitable shape for fitting the hand, and of Sullicient length down to the nger-engaging'shoul-y der to accommodate the entire hand;

tionf'and support of the valve housing is an elevational view of a blow-out and v `manner ,rubber hose I5,` which,

engaging the shoulder 5I) of the trigger, the washer is engaging the side of the ange which forms the shoulder 53 on the trigger, as shown rin Fig. 6. This causes the washer 3Il to bind against the trigger ange in such manner that plunger 23 constitutes a releasable latch. It is necessary not only to press upon the button 32, but to press on Y the trigger suiliciently to disengage the trigger I1,vand the'ring Itis-engaged in a groove I5 porcelain tubes 24 for insulation.

provides a housing for'the snap switchunit 25, which may con- 'vformed in' thehandle vcover plate 20.

Thecover lplate: 23 comprises a 'plate oi.'r sheet Ametal which is formed with a substantially 'square' guide aperture 2l andV with other apertures for receiving the screw bolts 22 which secure it on the-top cf the box-like formation I3.'` It also has apertures for passing the insulated leads 23 fwhich are covered with short The handle I0, being hollow,

sist of a snap switch of any suitable type. `One ception oi.

.type o f snapyswitchwhich may be used-lsdisclosed ini-Patent No. 1,889,259, issued November This si tenuta has a threaded bore 2s for rei iscrewfbolt 21 passing through the iorward vwall of vtheh'andle and, securing the switch-'unit in placer-The switch-funitjrnay have 'securedto it a substantially U'shaped supporting .member L28;A guffshaped metal a.member 23 slidabiy supports a' vslider 34, whierii's' adapted to engage the tumblerof the snap switch 25-and ac tuate the' snap switch, The slider 34 has a pair of rearwardly projecting anges 35, 35, the latter one being punched out of the body 34.

Flanges 35, 35 embrace a pin31, which pin is carried by the rearwardly projecting ears 38 of the trigger 39. The pin 31 is urged downwardly by a pair of coil springs 40, one located on each side of the U-shaped member-28, theends of each coil spring being hooked over the vpin 31. The opposite end of each coil spring is secured by a screw 4I to the U-shaped member 23. The ll- -shaped member 28 also carries a bracket 33, comprising a strip of metal, also secured by the screw 21 and extending upwardly into the body of the handlev I0. This bracket 33 has a rearwardly turned flange 42, which is secured by a screw bolt 43 to a supporting plate 44. Supporting plate 44 is secured in the box-like housing I3 by 4u.' pair o f screw bolts 45.

-Plate 44 and flange for passingthe square push rod 41. The bracket 33 has a pair of rearwardly projecting anges 43, with apertures for slidably supporting the plunger 29. Plunger 23 comprises a pin having a wash- -er 30 riveted on one end to retain it in the nanges 43. The other end of the plunger has a knob 32,v

and a' spring 3l is compressed between the knob 32 and a flange 48.

Spring downwardly in Fig'. 6 so engage flange 43. va shoulder 5I) so arranged that when' the trigger is pulled and the button 32 3l constantly urges the plunger 423 that washer 30 tends to 29 may engage the shoulderli to hold the trigger in closed. circuit position.

The trigger is normally in open circuit position, as shownin Fig. 2. and pulling on the'trigger.

the switch is closed by When the plunger 25 is 42 bothl have apertures 45 is pressed, the plunger switch to open position,

the spray gun whenever Vfrom under the washer 30; that is, the trigger must be pulled in far enough so that the shoulder clears the washer 30 before the trigger can in closed position, simultaneously pressing pulling and releasing the is held.

The same trigger 39 ,also controls an air valve in such manner that both of the sources oi power required for operating the spray gun trolled by the same trigger. This control is effected through the push rod 41, which extends downwardly through the apertures 45 and 2| and engages the slider 34. push rod extends upwardly through further guide apertures 2| in the supporting plates 5I, and is adapted to engage the stem 52 of an air valve 53. The air valve 53 is a substantially cylindrical body slidably mounted in a plug 54, which is carried by the metal body 55. Plug 54 may be constructed of brass and provided with a suitable are conseat 56 for engaging the complementary frusto valve body 23'. The plug 54 a bore 51 in the conical seat on the may be a close 'irctional iit in' body 53.

A coil spring 58 is contained in the bore 59 o! plug 54 and engages the valve body 53. The spring is placed under compression by a screw plug 60 which is threaded into the counterbore in the plug 54 and engages the end of the spring. The valve body 53 and seat 55 are so constructed that they have an initial clearance or opening s0 as to provide for the leakage of air through the air is turned on.

V This is a very important feature for effecting the cooling of the gun and preventing the nose of the gun from getting too hot.

A The body 55 is best shown in Fig. 4, and it comprises an inverted trough-shaped cast metal member, the walls of which have a multiplicity of apertures 5I. The member 55 has a depending body 52 in the trough, which is adapted to serve as an air conduit, having a bore 53,` which may be provided with a counterbore for receiving the air fitting 54. v

Conduit 53 communicates with a transverse bore 55 extending through the plug 54, and on the other side of the plug the conduit receives the end of a brass tube 56 for conducting air to The trigger 33,'.however, has Y a nozzle. The brass tube is secured in the body by means of a set screw 61, which engages the brass tube. The push rod 41 is adapted to engage the end of the valve stem 52 to open the air valve whenever the current is turned on. For this purpose theY push rod 41-is suitably spaced from the stern 52 to permit sufilcient movement of the trigger 39 to close the switch 25 before the valve ia opened. The switch 25 is then rst closed by the trigger 33, and continued movement of the trigger 35 serves only to open the air valve 53 to a greater or less amount. A large amount of air or a heavy pressure on the trigger serves to increase the amount of air discharged'and to increase The lthe torce and volume oi push rod, 41 to its position,

. ciently to provide'metal for a bore I l that passes` hook or other supporting member so that the n lain spool 8L r the spray. A mill amount of metal may be sprayed by merely-'openiing the valve 53 slightly with the trigger".

The valve spring Il also serves to return the rodis also actuated by gravi Thebodvjl'ls supported upon the handle 4Il by means'of a plurality of screwA bolts Il. The box-like formation i3 has its walls thickened at each corner sumthe heads of the screw bolts Il. The heads '1l'` engage the lowersuriace oi the plate 20, which is secured in place on the box Il by screw bolts 22. Thus the screw bolts Il may pass `.through the plate and be threaded into the boresIl inthe body 55.

Screw bolts 6I also support the-heat radiating spacers 12,` which are placed-on fthe screw bolts and interposed betweentheplates 2li,V Il.,

The upper plate il serves `as aclosure for the U-shaped trough members Blfv an curedin place by screw bolts B8,r l5 may also be provided with asupportin'g eye member comprising a pair'of sheetmetal angle members 13. 'Ihe feetvof these anglemembers are secured to the top of the body I5 by screw bolts 14 and their upwardlyl extending flanges are provided with registering apertures 14. 15.

"The apertures 15 may be used to'engage a gun may be hungup Iwhen hot or at any other time. Y v The valve housing has a substantially rectangular opening 16 at its forward or left end in Fig.v 2, boundedyby the trough-like walls 11. v3 This rectangular opening is adapted to receive the metal spacer 18, which is a tube located-on the brass tu-beY 6E. It also receives the porcelain `spacer 19, which is of suiiicient7size-to iit in the rectangular opening 16 and which has aJbore 80` for passing the brass tube 66. v

The porcelain spacer 1 also has a pair oi'. transverse apertures in the form 'of slots for passing the electrical conductors or leads 2l that exitend to the terminals Il of the heating element l?, 'Ihe heating element I2 comprises a helical coii of nichrome wire or other suitable resistance wire, which is wound helically upon a porce- I'he porcelain vspool 83 has hemi-cylindrical grooves 84 for receiving the coiled wire I2, and the grooves progress helically on the spool. One end of the heating coil wire is connected directly to ya terminal 8| at the right end, while the opposite end of the wire is led throughs, bore I5 in the spool to the other terminal l I.

The body 83 has a bore 8l formed in it for passing the brass air tube S6, and the heating element is supported by means of this tube.- y *The heating element is housed in a cast metal body l1, which has a substantially trough-likechamber I B in its interior. This chamber isopen at' the right end of Fig. 2 and has a substantially rectangular opening at that point for'receiving and engaging the at sides `of the spacer 10 as well as the flat sides Il carried by the end of the porcelain body Il. This prevents rotation of the porcelain body 83 on the tube,

`The trough-like chamber Il is closed at the bottom by means of a metal plate SII, which may' comprise a name plate of4 the tool, and is secured in .place by screw bolts 9|.

At its forward or left end (Fig. it) the heating: elementA housing is provided with an upwardly extending nose Il, which has a tapered bore 7s although-"the push 5 bore 94, which has the bronze nozzle ll ilxedly secured therein by a close frictional or drive ilt. The nozzle continues the taper of the bore 93 to a relatively ilne nozzle opening Ii, which determines the amount of metal sprayed from the gun.

The tapered boreA l! stick of suitable solder heat of the body is adapted to receive a 91, which is melted by l1 generated in the heating coil 82., The brass air tube 88 also terminates in a nozzle QI, the shape .of vwhich is shown in Fig. 7. This air. tube nozzle opening comprises an arc.. in shape, and is formed by flattening. the end ot the tube and curving it. It curves about the tapered frusta-conical end 99 ofthe air nozzle, when viewed in elevation vin Fig. 7. The forward wall IIIII 'of the heater element housing l1 is provided with an aperture lll for passing the air nozzle tube 66.

The end Il! of the nose of the gun is suitably curved `so thatit may be used as a trowel for smoothing out the solder after it has been placed and during the placing of the solder. It

will be understood that this nose surface III! is very hot and is adapted to remelt the placed solder, if necessary, in order to smooth it out and place it properly, but the solder is primariiy `placed by means of the spraying operation. I 'her edges of the heating element housing 81 Where they engage the valve housing 55 are provided at the points |03 with a plurality of small hem-spherical projections. These projections space these two metal members 4from each other and substantially reduce the conduction of heat from the member 81 to the member 5 5. 'I'hese two members are, however, secured together `by elongated screw bolts |04, seen in Fig.. 5, the bolts passing through the body 55 and being threaded into the body I1. f Y.

The operation of the spray gun is as follows: The gun is rst turned -on by pulling the trigger 39 and pressing the button 32 in such man.

this time some air will be heard to pass throughv the gun on account of the initial clearance given the air valve if the air tube is connectedvat this a disc sander, and the area sanded should extend to about one inch around the metal illl. All hammering and bumping out oi the area should be done before applying the metal. Use oi' acid or paint remover should be avoided `in all cases. f y

When the surface has been cleaned, a cold tinning compound. suitable for the-type of metal cleaned. is used to tin the surface of the metal. Various tinning compounds are on the market and may be used, but I deem it of great importance' to use the tinning compounds andk methods described in the co-pending application of Frank Osbern Albertson and Gustav A. Olsen, Ser. No. 80,372, led

and composition for spraying metal. The tinningcompound is applied by wetting a felt base n applicator and rubbing the compound into the II'." The tapered bore extends downwardly and slightly forwardly and terminates in a countertime. The surface of the metal to be sprayed must be sanded absolutely clean, preferably with- May 18, 1936, 0n Method` gun may be properly heated and connected to a source of air pressure of from 55 to 90 pounds improved structure and clearance which utilizesthe air pressure .toeot per square inch. It is now in condition to be spraying. This is done by means of a steel blowout tool, shown in Fig. 8. This clean-out tool HB has a tapered body III, fitting the metal well, and a laterally turned endl l2, with a ball'- shaped depression l I3.

The depression H3 may be disposed in front of the air nozzle, as shown in Fig. 9, to force air from that nozzle up into the metal well to blow it out.

The solder' stick is then fed into the well of the heat gun, and as it is melted it is sprayed by means of the compressed airj from the nozzle 9B. Pressure of the trigger controls the supply of the air, and when the trigger is released both the heat unit and the air are automatically shut oiT. This avoids damage to the gun. The nose of the gun should notl be held toofar away from the work, and the best results are accomplished by holding the gun at from one to two inches from the work.

'I'he best way to spray the metal filling is rst to spray a thin layer of metal, covering the entire tinned surface. i in circular motion around the outer edge and toward the center. The air should be kept on all the time while feeding metal to the gun. This tends to prevent blowing a blotch of molten metal on the job, and if a lblotch occurs it should be removed. When more than one place is to be repaired, the places should be tinned and sprayed one at a time. The spray dust resulting from one job and covering thesecond prepared surface -should -be wiped off before tinning the second place. n

The metal filling should be sanded down to a feather edge, and in placing the metal it should be built up to such a depth th-at it can -be sanded down to a smooth surface. It is better to use suilicient metal so that it is not necessary to try to add metal after the surface has lbeen once polished. The metal adheres better when it is all applied in one job, and it is dilcult to get sprayed metal to adhere to metal which has been polished. l

This can now be done, however, -by means of smoothing the lead surface and making two or more thorough applications of the tinning compound to the lead surface and immediately spraying metal on it as described in said copending application.

The gun should be carefully cleaned, particularly at the ,metal well, while it is hot, and the nozzle should -be blown outy at that time, after all metal has been removed from the well.

The .present metal spray gun is adaptedA to be used to carry out an improved method of repair of automotive-fenders and bodies. The present gun has .a more eifective control than -any of the spray guns of any type of the Iprior art, and both the air and heat are controlled by the trigger. The metal sprayed by this gun is so cool that it may be directly sprayed upon anything without heating the body to which the. spray is applied. Thus the panels of metal composing the vehicle oody are not heated and warped, and there is no The spray should be moved by means of the `'valve fa cooling. It is alsoadapted to be used forca: long period of time without overheatingl or damage to any pf its parts.

While I have illustrated and described a pre-g ferred embodiment of my invention, many modifications may be made without departing from the spirit of the invention, and I do not wish to be limited to the precise details of construction set forth, but desire to avail myself of all changes within the scope of the appended claims.

Having thus described my invention, what I claim asv new and-'desireto secure by United States Letters Patent is:

1. In a metal spray gun, the combination of an electric heating element with a body having a metal well with a discharge aperture, an air nozzle for spraying molten metal discharged through said aperture, electric switch means for. controlling the supply of electric current to said heating element, valve means for controlling the supply or' air to said air nozzle, and common controiling means whereby the air supply and the heat of the element are both controlled from the same manual means, said air valve having an initial clearance .permitting the leakage of air through said gun and nozzle to eiect a cooling of said gun.

2. In a metal spray gun, the combination of an electric heating element with a body having a metal well with a discharge aperture, an air nozdanger of igniting inflammable material used under the metal body for insulation.

The present gun is kept cool by means of its zle for .spraying molten metal discharged through said aperture, electric switch means for controlling the supply of electric current to said heating element, valve means for controlling the supply of air' to said air nozzle, and common controlling means whereby the air supply and the heat of the element are both controlled from the same manual means, said common controlling means being arranged in such manner that the initial movement of said controlling means closesl the electric circuit and further movement of said controlling means controls the lopening of said air valve.

3. In a metal spray gun, the combination of an electric heating element with `a body having a metal well with a discharge aperture, an air noz- 'zle for spraying molten metal discharged through said aperture, electric switch means for controlling the supply of electric current to said heating element, valve means for controlling the supply of air to said air nozzle, common controlling means f whereby the air supply and the heat of the element are both lcontrolled from the same manual means, and means for latching said common controlling means with the switch in closed position to heat up the gun.

4. In a metal spray gun, the combination of an electric heating element with a body having a. metal well with -a discharge aperture, an air nozzle for spraying molten metal discharged through lsaid aperture, electric switch means for controlling the supply of electric current to said heating element, valve means for controlling the supply of air to said air nozzle, common controlling means whereby the air supply and the heat of the element are both controlled from the same manual means, said common controlling `means Ibeing arranged in such manner that the initial movement of said controlling means closes the electric circuit and further movement of said controlling means controls the opening of said air valve, and means for latching said common anais controlling means the switch in position to heat unthc 5. In a metal spray gun, the combination of l a supporting handle with a plurality of posts for supporting a gun body,.said posts supporting said gun body in spaced relation to said handle, a gun body comprising means for housing an air valve, and means for housing an electric heatingelement, said latter means being constructed of heat conducting metal and being provided with a metal well whereby a supply oi metal inserted in said well is melted to be sprayed from said gun. l

` `6. In a metal spray gun, the combination of a supporting handle with a plurality of posts for supporting a gun body, said posts supporting ing with a counterbore and a bronze metal nozzle located in said counterbore, said body having a said gun body in spaced relation to said handle,

a gun` body comprising means for housing an air' valve, and means for housing an electric heating element, said latter means being constructed of heatconducting metal and being provided with a metal well whereby a supply ofl metal inserted in said well is melted to be sprayed from said gun, and said metal well having a metal nozzle constructed of metal having a high melting point.

7. In a metal spray Igun, the combination oia supporting handle with' a' plurality of posts for supporting a gun body, said posts supporting said gun body in spaced'relation to said handle, a gun body comprising means for housing an electric heating element, said lattermeans be-v ing constructed of heat conducting metal and being provided with a metal welll whereby a' supply of metal inserted in said well is meltedto be sprayed from said gun, said metal well having a metal nozzle constructed of metal having a high melting point, and an air tube controlled by and havinga nozzle disposed in proximity to said well. nozzle.

8. In a metal spray gun, the combination of a supporting handle with a plurality of posts for substantially trough shaped chamber in its lower side provided with a closure plate, a porcelain support locatedin said chamber, a heating element on saidsupport, said porcelainV support and said chamber having complementary engaging shoulders to prevent rotation oi said porcelain support in said chamber, a second metal body iixedly secured to said nrst metal body and carrying the. .rst metal body, and means between. said metal bodies Vfor spacing them from each other to reduce the heat conduction between said metal bodies.

11. I n a metal spray gun, the combination of a heat conducting body i'ormed with a downwardly tapering metal well, said metal well communicating with a counterbore and a bronze metal nozzle located in said counterbore, said body having Y a substantially trough shaped chamber in its lower side provided with a closure plate,A a porcelain support located in said chamber, a heating said valve and extending through said gun body element onsaid support, said porcelain support and said chamberhaving complementary engaging shoulders to prevent rotation of said porcelain support in said chamber, a second metal body ilxedly secured to said ilrst metal body and carrying the iirst metal body, .means between said metal bodies for spacing them from each.

other to reduce the heat conduction between said metal bodies, said second metal body havingk an air tube ilxedly carried thereby, said air tube extending throughsaid porcelain support and carrying the. porcelain support, and .a nozzle carried by said metal tube adjacent said well nozzleto eiect a spray of metal discharging from said well nozzle.l

12. In a metal spray gun, the combination of a heat conducting body formed with a downwardly l tapering metal well, said metal well communicating with a counterborev and a bronze metal noz- 1 zle located in said counterbore, said body having supporting a gun body, said posts supporting said gun body in spaced relation to said handle, a gun body comprising means for housing an air valve, means for housing an electric heating element, said latter meansbeing constructed of heat conducting metal and being provided. with a metal well whereby a supply of.r metal inserted in said well` is melted to be sprayed from said gun, said metal well having a metal nomle constructed of metal having aL high melting point, an air tube controlled by said valve and extending through said gun Vbody and having a nozzle disposed in proximity to said well nozzle, and common controlling `means carried by said handle for controlling the opening of said valvey and the-connection oi saidl heating element to a source of electric power,

9. In a metal spray gun, the combination of a heat conducting bodyi'ormed with a downward- A ly tapering metal well, said well communicating with a counterbore and af bronze metal nomle located in said counterbore, said body having a substantially trough shaped chamber in its lower side provided with a closure plateiand a porcelain support located .in said chamber and a heating element on said support, said porce- 4. lain supportand said chamber having complementary engaging shoulders to prevent rotation olsaidporcelain support in said chamber.

10. In a-metal spray Sun.: the combination of a heat conductlngbodyformed with va. downwardly tapering metal welLsaid metal well communicat-v means for controlling the connection oi' a substantially trough shaped chamber in its lower side provided with a closure plate, a porcelain support vlocated in said chamber, a heating element on said support, said porcelain support" and said chamber having complementary'engaging shoulders to prevent rotation of said porcelain support in said chamber, a second metal body xedly secured to said rst'metal body and carrying the ilrst metal body, means between said metal bodies for spacing them from each other to reduce the heat conduction between said metal bodies, valve means for controlling the ow of air through said Vmetal tube, and electric switch the source of heat supplied to saidlelement.

13.` In a metal spray gun, the combination oi' a heat conducting body formed with a downwardly tapering metal well, said metal well communicating with.a counterbore and a bronzemetall nozzle located in said counterbore, said body. having a substantially trough shaped chamber in its lower side provided with s closure plate,

'a porcelain support located in said chamber, a

heating element on said support, said porcelain st nlhport and said chamber having complementary engaging shoulders to prevent rotation of said porcelain support in said chamber, a.' second metal body tlxedly secured to said iirst metal body andcarrying the nrst metal body, means between said metal bodies for spacing them from each other to' reduce the heat conduction between said metal bodies, saidewnd metal rbody having anairtubexedly-carried thereby,saidairtube by said metal tube adjacent said well nozzle to effect a spray of metal discharging from said well nozzle, and a common trigger for controlling both said valve means and said electric switch means.

14. In a metal spray gun, the combination of a heat conducting body formed with' a downwardly tapering metal well, said metal well communicating with a counterbore and a bronze metal nozzle located in said counterbore, said body having a. substantially trough shaped chamber in its lower side provided with a closure plate, a' porcelain support located in said chamber, a heating element on said support, said porcelain support; and said chamber having complementary engaging shoulders to prevent rotation of said porcelain support in said chamber, a second metal body xedly secured to said rst metal body and carrying the iirst metal body, means between said metal bodies for spacing -them from each other to` reduce the heat conduction between said metal bodies, said second `metal body fhaving an air tube xedly carried thereby, said air tube extending through said porcelain support and carrying the porcelain support, a. nozzle carried by said metal tube adjacent said Well nozzle to effect a 'spray of metal discharging from said well nozzle, a common trigger for controlling both said valve means and said electric switch means, and latching means for latching said trigger in closed circuit position. Y

15. In a metal spray gun, the combination of a handle with a gun body, said body comprising an elongated metal member having an operating nose at one end provided with a downwardly tapered metal well, a tubular extension for said metal well and having a metal discharging opening, said body being formed with a heater chaml ber, an electric heating element in said chamber for heating said body and the metal inserted in said well, and an ai-r supply tube carried by said body and extending into said body in proximity to said heating element whereby the air in said tube is also heated by said heating element, and an air nozzle carried by said air tube in position to discharge air across the end of said metal well, to effect a4 metal spray by means of heated air.

16. In a metal` spray gun, the combination of a. handle with a gun body, said body comprising an elongated metal member which is provided with a downwardly extending and tapered metal well at one`\ end, said body being supported on said handle atits opposite end and comprising a pair of separate metal parts, means for securing said metal parts together, and means for spacing said metal parts ,from each other for the purpose of diminishing heat transmission by conduction from one part of said body to theother, said body having a chamber for receiving an electric heating element and having an air supply tube provided with a nozzle disposed to cause a discharge of air across the end of said metal well.

17. In a metal spray gun, the combination of `a handle with a gun body, said body comprising an elongated metal member which is provided with'a downwardly extending and tapered metal well at one end, said body being supported on said handle at its opposite end and comprising a pair of separate metal parts, means for securing said metal parts together, and means for spacing said metal parts from each other for the purpose of diminishing heat transmission by conduction from one part of said body to the other, said body having a. chamber for receiving an electric heating element and having an air supplytube -provided with Va nozzle disposed to cause a dis-" charge of air across the end of said metal well, said 'air tube being constructed of metal and passing -through a part of said gun body in proximity to said heating element whereby the air is adapted to bev heated and the metal sprayed with preheated air. l

18. In a metal spray gun, the combination of a handle with a, gun body. said body comprising an elongated metal member which is provided with 1a. downwardly extending and tapered metal well at one end, said body being supported on said handle at its opposite end and comprising a pair of separate metal parts, means for securing said metal parts together, and lmeans for spacing said metal parts from each other for the purpose 0f diminishing heat transmission by conduction' from one part of said body to the other, said body having a chamber for receiving an electric heating element and lhaving an air supply tube provided with a nozzle disposed to cause a discharge of air across the end of said metal well, said handle being connected to said body by a plurality of posts for diminishing the heat conduction to said handle from said body, and means carried by said posts for spacing said body from said handle.

19. In a metal spray gum-the combination of a handle with a gun body, said body comprising an elongated metal member which is provided with a downwardlyextending and tapered metal well at one end, said body being supported on said handle at its opposite end and comprising a pair of separate metal parts, means for securing said metal parts together, and means Afor spacing said metal parts from each other for the purpose of diminishing heat transmission by conduction from one part of said body to the other, said body having a chamber for receiving an electric heating element and havi'ng an air supply. tube provided with a nozzle disposed to cause a discharge of air across the end of said metal well,

' said handle being connected to said body by a.

plurality of posts for `diminishing the heat conduction to said handle from said body, and means carried by said posts for spacing said body from said handle, and a Iplurality of heat radiating members carried by said posts, said heat radiating members being arranged for the circulation of air between' said heat radiating members.

20. In a metal spray gun, the combination of a supporting handle with a spray gun body comprising a pair of metal members, one of said metal members being provided with a metal well extending downwardly into said body, and also having an air nozzle adapted to discharge air transversely to the end of said Well, said members comprising said gn body being secured together in spaced relation, with spacing means between them to diminish heat conduction between s aid bodies, and the other of said metal bodies being provided with ventilation openings for' permitting the circulation of cooling air through the otherof said metal bodies."

21. A gun for spraying metal, comprising a body having therein a heating element and a receiving space for the metal to be sprayed, said space being disposed operatively adjacent the heating element and having a discharge oriiice for the melted metal, means to project sprayinguid relative to the discharge orice in a manner to spray metal therefrom, a handle, and means operatively adjacent the' 'the metal to interposed between one end of the handle and an adjacent surface of the body, including a plate, each major face of which is generally spaced from the adjacent surfaces of the handle and body respectively a short distance to provide for free passage of air across said surfaces and the faces of the plate, and means to secure the plate,

handle and body together substantially in fixed relationship.

22. A gun for spraying metal, comprising a main 'supporting frame including: a laterallyprojecting handle, a heater housing' supported on `one end of the frame closely adjacent and in spaced relation thereto to provide a heat-insulation air-gap. a heating element in said housing, a receptaclefor metalv to be melted and having .an electric heating element therein and in alignment with `to ,be sprayed, a

alignment with the nozzle having a crescent-shaped oriiice for spraying iiuid in the form of a trough around and across the orice of the tip to entrain and spray the melted metal from the tip.

26. In a gunior spraying metal, a metal body of the metal of the body, and means including a I nozzle having an arc-shaped orice for spraysprayed also located in' said housing adjacent the element and having a discharge nozzle which is directed downwardly in the operating position of the gun, and means carried on the frame for conveying fluid and projecting the same generally horizontally and across said discharge nozzle in a manner to spray thermetal therefrom.A

23. In a ins having a discharge orifice,

assembly including a receptacle for metal a metal. housing in gun for spraying metal, a metal-heatwhich said receptacle is formed, an electric heating element in the housing, means to supply current tothe element, and a spraying-fluid conveyor tube located 'in a through bore of the housing but generally out of contact with the metal of. the housing and having a discharge nozzle effect at one end of the bore in spraying relationship to the discharge orice of the receptacle.

24. In a gun for spraying metal, a metal housing having a heating element therein and a 'substantially vertical well formed in the housing element `for receiving be sprayed and passing the melted metal downwardly therefrom, a tubular tip of non-erodible metal secured in the housing in alignment with the well and projecting free from` -the metal of the housing, and

means to project spraying iluid around and across the orliice of the tip to entrain and spray the metal from the tip. i

25.1In a guni'or spraying metal. a metal housing having a heating element therein and a well formed inthe housing adjacent theyeiement for containing the metal to be sprayed, atubular tip connected together ceptacle.

ing iiuid in the form of a trough around and across the metal discharging from the orioe of thetip to entrain'and spray the melted metal issuing from the tip.

27. In a gunfor spraying metal, a metal heating assembly includingy a metal body having a receptacle formed therein tacle having a discharge orince, an electric heating element located in the body, means to supply current to said element. andv a spraying Iiuid conveyor tube located in a bore in saidbody and projecting therefrom 'and having a discharge nozzle located at one end of said tube in spraying relationship to the discharge orice of the rebodycomprising which is provided and tapered metal charg pel'tllre, Said body and handle being by a of supporting metal heat radiating plates carriedbysaidpostsinspacedrelationtoeach other for diminishing heat um on from said body to 'said handle, an electric heating element in said body, and an air supply eonduitvinv said body, said conduit terminating in a tubular metal member posts. a plurality of o. madison.

well and projecting tree from the metal of the housing,land means including a bodysecuredinsaidbody Ifonxnetal. said recepl spray glm, the combination of a metal handle with well at one end, having a dis--y proiectingfrom said body in. 

